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https://dev.mysql.com/doc/refman/8.0/en/data-change-optimization.html
This section explains how to speed up data change statements: INSERT, UPDATE, and DELETE. Traditional OLTP applications and modern web applications typically do many small data change operations, where concurrency is vital. For inserting and ...
https://dev.mysql.com/doc/refman/8.0/en/data-dictionary-usage-differences.html
Examples: ANALYZE TABLE fails because it updates table statistics, which are stored in the data dictionary. ALTER TABLE tbl_name ENGINE=engine_name fails because it updates the storage engine designation, which is stored in the data dictionary. (To ... Use of a data dictionary-enabled MySQL server entails some operational differences compared to a server that does not have a data dictionary: Previously, enabling the innodb_read_only system variable prevented creating and dropping tables only for the InnoDB storage ...
https://dev.mysql.com/doc/refman/8.0/en/disk-issues.html
RAID N can be a problem if you have many writes, due to the time required to update the parity bits. That skips updates to the last access time in inodes on the file system, which avoids some disk seeks. On many operating systems, you can set a file ... This section describes ways to configure storage devices when you can devote more and faster storage hardware to the database ...
https://dev.mysql.com/doc/refman/8.0/en/dynamic-format.html
A row can become fragmented (stored in noncontiguous pieces) when it is made longer as a result of an update. For example, if you update a row with information that extends the row length, the row becomes fragmented. A dynamic row is linked whenever ... Dynamic storage format is used if a MyISAM table contains any variable-length columns (VARCHAR, VARBINARY, BLOB, or TEXT), or if the table was created with the ROW_FORMAT=DYNAMIC table ...
https://dev.mysql.com/doc/refman/8.0/en/explain-output.html
No matching rows after partition pruning (JSON property: message) For DELETE or UPDATE, the optimizer found nothing to delete or update after partition pruning. The EXPLAIN statement provides information about how MySQL executes statements. EXPLAIN ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-fulltext-index.html
The caching and batch flushing behavior avoids frequent updates to auxiliary index tables, which could result in concurrent access issues during busy insert and update times. Specifically, updates and insertions on a full-text index are processed at ... Full-text indexes are created on text-based columns (CHAR, VARCHAR, or TEXT columns) to speed up queries and DML operations on data contained within those ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-memcached-benefits.html
You can control frequency of writes to achieve higher raw performance when updating non-critical data. You can stop and start the memcached server without losing updates made to cached data. Because you can access the underlying data through SQL, ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-row-format.html
As more rows fit into a single disk page, queries and index lookups can work faster, less cache memory is required in the buffer pool, and less I/O is required to write out updated values. Reserving fixed space for NULL values permits columns to be ... The row format of a table determines how its rows are physically stored, which in turn can affect the performance of queries and DML ...
https://dev.mysql.com/doc/refman/8.0/en/keyring-hashicorp-plugin.html
Create a new file named mysql.hcl with the following content: path "kv/mysql/*" { capabilities = ["create", "read", "update", "delete", "list"] } Note kv/mysql/ in this example may need adjustment per your local installation policies and security ...
https://dev.mysql.com/doc/refman/8.0/en/mysql-cluster-limitations-syntax.html
ON UPDATE CASCADE is not supported when the reference is to the parent table's primary key. This is because an update of a primary key is implemented as a delete of the old row (containing the old primary key) plus an insert of the new row (with a ... Some SQL statements relating to certain MySQL features produce errors when used with NDB tables, as described in the following list: Temporary ...